Please follow the below steps to add a refinement in the refinement panel of the sharepoint page.

Extract XML of the Filter Category Definition

we need to extract the xml of the Filter Category Definition from the existing default refinement panel.

A. In your browser, navigate to the results page URL:

http://SiteURL/Pages/results.aspx

B. On the Site Actions menu, click Edit Page.

C. In the Refinement Panel Web Part, click the edit arrow to display the Web Part menu, and then click Edit Web Part. This opens the Web Part tool pane.

D. In the Refinement section, clear the Use Default Configuration check box.

E. In the Refinement section, click the ellipsis (…) button for the Filter Category Definition field.

This opens the Text Entry window for the Refinement Web Part's FilterCategoriesDefinition property. You can modify the XML directly in this window; however, you may find it easier to copy the code to a file.

Edit the XML in Visual Studio

Now we need to edit the given xml in visual studio preferably. You will find a filters already present for the Result Type, Site, Author,etc by default. We will try to add our own filter in it.

We will add ‘Content Source’ category filter to it, so that we can filter based on the content source from which the result was crawled.

Save back the edited XMl of FilterCategoriesDefinition in webpartCopy back the edited xml to the webpart’s FilterCategoriesDefinition property and click ok. Now our webpart is ready to use content source as a filter. But main catch here is that content source property is not retrieved in the ContentCoreResult Webpart without which our filter will be of no use.

Add the column for Content SourceAdd the column for “Content Source” in the ContentCoreResult webpart

A.In your browser, navigate to the results page URL:

http://SiteURL/Pages/results.aspx

B. On the Site Actions menu, click Edit Page.

C. In the Content Core Result Web Part, click the edit arrow to display the Web Part menu, and then click Edit Web Part. This opens the Web Part tool pane.

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